Function test_encode_cf_timedelta_units_change

xarray/tests/test_coding_times.py:1793–1811

(use_dask)

@pytest.mark.parametrize("use_dask", [False, pytest.param(True, marks=requires_dask)])
def test_encode_cf_timedelta_units_change(use_dask) -> None:
    timedeltas = pd.timedelta_range(start="0h", freq="12h", periods=3)
    encoding = dict(units="days", dtype=np.dtype("int64"))
    variable = Variable(["time"], timedeltas, encoding=encoding)

    if use_dask:
        variable = variable.chunk({"time": 1})
        with pytest.raises(ValueError, match="Timedeltas can't be serialized"):
            conventions.encode_cf_variable(variable).compute()
    else:
        # In this case we automatically modify the encoding units to continue
        # encoding with integer values.
        with pytest.warns(UserWarning, match="Timedeltas can't be serialized"):
            encoded = conventions.encode_cf_variable(variable)
        assert encoded.attrs["units"] == "hours"
        decoded = conventions.decode_cf_variable(
            "name", encoded, decode_timedelta=CFTimedeltaCoder(time_unit="ns")
        )
        assert_equal(variable, decoded)


@pytest.mark.parametrize("use_dask", [False, pytest.param(True, marks=requires_dask)])